What’s Vulnerable › Vulnerabilities

CVE-2019-11758

• Severity: high (CVSS 8.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-01-08 · updated 2026-06-17
• Weakness: CWE-787

Description

Mozilla community member Philipp reported a memory safety bug present in Firefox 68 when 360 Total Security was installed. This bug showed evidence of memory corruption in the accessibility engine and we presume that with enough effort that it could be exploited to run arbitrary code. This vulnerability affects Firefox < 69, Thunderbird < 68.2, and Firefox ESR < 68.2.

Affected products

• Canonical Ubuntu Linux: 16.04
• Mozilla Firefox: before 69.0 — fixed in 69.0
• Mozilla Firefox ESR: before 68.2 — fixed in 68.2
• Mozilla Thunderbird: before 68.2 — fixed in 68.2

How to fix

Upgrade to a fixed version: Mozilla Firefox 69.0; Mozilla Firefox ESR 68.2; Mozilla Thunderbird 68.2. Check the vendor advisory for mitigations.

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=1536227
• https://usn.ubuntu.com/4335-1/
• https://www.mozilla.org/security/advisories/mfsa2019-25/
• https://www.mozilla.org/security/advisories/mfsa2019-33/
• https://www.mozilla.org/security/advisories/mfsa2019-35/
• https://bugzilla.mozilla.org/show_bug.cgi?id=1536227
• https://usn.ubuntu.com/4335-1/
• https://www.mozilla.org/security/advisories/mfsa2019-25/
• https://www.mozilla.org/security/advisories/mfsa2019-33/
• https://www.mozilla.org/security/advisories/mfsa2019-35/

Get alerted when CVE-2019-11758 or the next vulnerability affects your stack